Seven to eight years. According to the inquiry of Zhengshukang official website, the service life of Zhengshukang concentrated shoulder and neck massager is 7 to 8 years. It should be noted that massagers cannot be used continuously for a long time. Zhengshukang brand belongs to Yongkang Ricky Company, which mainly deals in shoulder music massager, bath apparatus, sauna equipment, yuba, steam bath apparatus, sitz bath apparatus, portable ironing machine, yuba and other products.